Reason and Revelation
Reason and Revelation
At the center of Thomas’s philosophical theology, from beginning to end, is his understanding and application of the relationship between that which can be gleaned by way of “natural reason” and that which is given in God’s revelation. There is no debate that Thomas made this distinction, but there remains significant and often strident debate among Thomists as to the proper structure of this distinction. More on that below. First, however, the distinction. According to Thomas, the distinction is this:
Now in those things which we hold about God there is truth in two ways (duplex veritatis modus). For certain things that are true about God wholly surpass the capability of human reason, for instance that God is three and one: while there are certain things to which even natural reason can attain, for instance that God is, that God is one, and others like these, which even the philosophers proved demonstratively of God, being guided by the light of natural reason.2
For Thomas, then, there is a “twofold truth of divine things.”3 The first, in methodological order, consists of all that can be known about God by natural reason, and the second consists of those divine things that can be known only by revelation. Thus:
While then the truth of the intelligible things of God is twofold, one to which the inquiry of reason can attain, the other which surpasses the whole range of human reason, both are fittingly proposed by God to man as an object of belief.4
Thomas thinks that natural reason forms the foundational structure of which revelation is the superstructure, in part because of his understanding of certain biblical passages. For example, in response to his question, “Whether God Can Be Known in This Life by Natural Reason?” Thomas first quotes Romans 1:19 (in his sed contra),
It is written (Rom. 1:19), That which is known of God, namely, what can be known of God by natural reason, is manifest in them.5
He then continues with this explanation of that passage:
Our natural knowledge begins from sense. Hence our natural knowledge can go as far as it can be led by sensible things. But our mind cannot be led by sense so far as to see the essence of God; because the sensible effects of God do not equal the power of God as their cause. Hence from the knowledge of sensible things the whole power of God cannot be known; nor therefore can His essence be seen. But because they are His effects and depend on their cause, we can be led from them so far as to know of God whether He exists, and to know of Him what must necessarily belong to Him, as the first cause of all things, exceeding all things caused by Him.6
His understanding of Romans 1:19, then, is that the human intellect, that is, “natural reason,” is able, by itself, to demonstrate the existence of God and gain some knowledge of him.
In another context, Thomas again sees the passage in Romans as referring to natural reason:
Three things lead us to believe in Christ. First of all, natural reason: “Since the creation of the world the invisible things of God are clearly known by the things that have been made” (Rom 1:20).7
One reason why Thomas thinks of human reason this way is found in his commentary on John 1:9 (i.e., “The true light, which gives light to everyone, was coming into the world”). In support of his view, Thomas first quotes from Theophylact:
The intellect which is given in us for our direction, and which is called natural reason, is said here to be a light given us by God.8
Then later he adds this:
However, if we bear in mind these distinctions and take “world” from the standpoint of its creation, and “enlighten” as referring to the light of natural reason, the statement of the Evangelist is beyond reproach. For all men coming into this visible world are enlightened by the light of natural knowledge through participating in this true light, which is the source of all the light of natural knowledge participated in by men.9
Thomas surmises, on the basis of these passages, that all people have and use, in identical ways, the light of natural reason, which is had by virtue of some kind of “participation” in the “true light.” We should make it clear here that Thomas does not think that the “enlightening” of which John speaks necessarily includes divine truth or content. Instead, “enlightening” means that we are all able to reason in the same ways. In Thomas’s construal, then, there are divine things known by natural reason, and thus available to all people, and there are divine things known by way of revelation, and thus meant only for the faithful.
We need also to mention here, though this gets little attention among Thomists, that there is a kind of knowledge mentioned by Thomas that is distinguished from these two primary kinds. Though Thomas’s “twofold” knowledge is predominant in his thinking and writing, he affirms, as well, a third category:
Now there is a threefold knowledge of God. One knowledge is that by which he is known only in his effects, as if, insofar as someone knows being or something created, he has some sort of knowledge of God the creator and his creation of it, [namely an implicit knowledge]; and this knowledge is in all men naturally and from the beginning. Another knowledge is that by which God is considered in himself yet nevertheless is known through his effects, insofar as someone proceeds from the knowledge of his effects to the knowledge of God himself. And this can be had through the inquiry of natural reason, although not immediately. And it was thus that the philosophers and other wise men arrived at knowledge of God, to the extent that it is possible to attain it. The third knowledge is that by which he is known in himself and in those things that exceed all proportion to his effects. And this knowledge is neither naturally in men, nor had through the inquiry of natural reason, but had through an infused supernatural light. According to this threefold knowledge, a threefold love is found. One is that by which God is loved in his effects, insofar as when I love a creature I am said to love God. Another love is that by which God himself is loved on the basis of his effects, and this love is had through inquiry, as when someone knowing God from his effects loves him.10
In this citation, Thomas affirms a kind of knowledge that all people have by virtue of being creatures in the world. This knowledge is “implicit,” in that it is had neither by natural reason nor by revelation. It is a knowledge of “being” or of “happiness” (on which more is said below).
Significant as this third kind of knowledge is, it garners little to no respect in Thomas’s system. The reason for its nominal status is that the content of this implicit knowledge is invariably vague and general. In the citation above, the content consists of “being [i.e., existence] or something created.” In the Summa contra gentiles, Thomas makes this point more clearly:
For man knows God naturally in the same way as he desires Him naturally. Now man desires Him naturally in so far as he naturally desires happiness, which is a likeness of the divine goodness. Hence it does not follow that God considered in Himself is naturally known to man, but that His likeness is. Wherefore man must needs come by reasoning to know God in the likenesses to Him which he discovers in God’s effects.11
So, the first kind of this “threefold knowledge” that Thomas affirms holds little to no place in his epistemological structure. It is knowledge that shows itself in a vague and ambiguous idea, concept, or desire. The best it provides is an amorphous, indirect connection to who God is. For this reason, the “twofold” knowledge of God of which Aquinas speaks is almost always highlighted by Aquinas and his followers. The first kind of knowledge, though universal and implicit, contains very little real content.
In his discussion of reason and revelation, then, we see three different kinds, or modes, of knowledge:
(1) The first is obscure and indirect, having as its objects those things which also, even if in an ambiguous and confused way, comport indirectly with aspects of God’s character or of man’s existence generally. This, it seems, is what Thomas means when he asserts, as quoted above, that the “true light” of which John 1:9 speaks “is the source of all the light of natural knowledge participated in by men.” In other words, because we are creatures, and because we know that we and other things exist, we have a general knowledge of “being” and of the fact of creation. This is all that such an implicit knowledge can give.
(2) The second, more prominent, mode of creaturely knowledge is that which is gained through demonstration by way of our “natural reason.” Here Thomas makes it clear that natural reason includes that which philosophers have employed. The fact that God’s existence, and something of his character, can be proved is obvious because philosophers have shown it to be so.
(3) Third, there is knowledge that comes by revelation. This knowledge can supersede what is discerned by natural reason, but it might also include, for the faithful who are not inclined toward philosophical or demonstrative knowledge, the knowledge that can be gained by natural reason.